Moreover, when ACE2 was ectopically expressed in HDFs (ACE2-HDFs) to a level comparable to that in HepG2 cells, a human cancer cell line that can be infected with SARS-CoV-2, the HDFs became infectable with SARS-CoV-2 (Fig. 1b–d and Extended Data Fig. 1a,b). Here, ACE2 is linked to cancer.